Remove assembly coded log2 function

As we move to supporting other systems we need to get rid of assembly
where we can. The log2 function in src/lib is identical to the assembly
one (tested for all 32-bit signed integers :-) and takes about 10 ns
to run as opposed to 5ns for the non-portable assembly version. While speed
is good, I think we can spare the 15 ns or so we add to boot time
by using the C version only.

Change-Id: Icafa565eae282c85fa5fc01b3bd1f110cd9aaa91
Signed-off-by: Ronald G. Minnich <>
Tested-by: build bot (Jenkins)
99 files changed